Fluorescent light for display cabinets



Patented Jan. 9, 1951 FLUORESCENTLIGHT FOR DISPLAY CABINETS Herbert Grindstaffzand Floye J. .Bearden,

Los. Angeles, Calif...

Applicatibn'lluly zfl, 1948, SerialNo. 40,096

This invention relates generally to lighting units for display cabinets, and findsone of its chief advantages in its adaptability for provid ing fluorescent lighting for refrigerated display cabinets.

In the lighting of 'such display cabinets, it has been difficult to use fluorescent light tubes because of the d'ifii'culties of' installing and" changing'the tubes and also because the tubesare'noh mally exposed to injury by people placing articles in and-removing them fromthecabinet;

It is one of the chief objects of our inventionto provide a lighting unit which will overcomepresently preferred embodiment illustrating one of the physical forms in which ourinvention may be carried out. In the drawings:

Fig. 1 is a sectional view of a display cabinet showing, in side elevation, our unit mounted therein;

Fig. 2 is a section taken on line 2-4 of Fig: 1'';

Fig. 3 is a longitudinal sectional view of aportion of our unit, some. parts being shown in. elevation;

Fig. 4 is a sectiontaken online t-dbfFig. '3; and

Fig. 5 isv a front elevation of a typical display cabinet in which our unit may be mounted.

Referring. now to the drawings, the reference letter C generally denotes a display cabinet, such as a refrigerated cabinet, and the vvnumeral 5. gen.- erally denotes our lighting unit.

terial E6. The particular construction of the doors and doorways, however, does notiorn'r any part of our-invention, since the invention issueceptible of being mounted in practically any cabinet.

A conventional power pack is. housed within a casing 20. secured to the inside of the cabinet:

immediately above. dividing posts; 9; being:-

6.:Gl'aims: (01. 240-6) the socket.

connected to an electrical; source through wires W. To the inside of the casing 2.0 there is secured a1 four-outlet socket member 2:! providing sockets'for-reception:of?thefour L-shaped prongs 22' of a twist: lock connector 25.

We fix to the floor, at a point directly beneath the socket, a positioning plate orferrule 2'5 having a peripheral flange 211a fcrthe purpose to be described. the ferrule being secured: as by screw 23.. It will be observed that the ferrule 21 and the power paclc are fixedly mounted in. the cabinet.

Between the socketand the ferrule We mount, in. the manner. now to. be, described, armor tube 30. which. preferably is of transparent plastic and has its outer. half, coated with a lightra. flectiye coating 3!. (Fig. 4). The. tube. has a bottom wall. 32 but. is, open at its top. end. The, side wall of. this tube atits-top-end. portion. is longitudinally slotted as shown at at. for the. purpose to be. described,

Within the tube 311 We slidably mount a. light unitconsisting ofend. disks 35, 3.6., each carrying a socket 35a, 35a, for the reception. of theendsv of;a, fluorescent light tube 31'. The armor tube. is shorter than, the distance between, socket 2i. and the ferrule 2'! so. that, when thelower end of. thearmor tube is positioned within the. ferrule the'upper. end of the. tube terminatesshort of A tube. or cable, 40,. which is. sub? stantially rigid, is-irictiona11y fitted. at its. ends. in openings in. the, respective disks, being securedagainst escape therefrom by meansof set screws M, 42. The screw 62. prbjects atits outer. endv radially from the disk 35,. andis. adapted to slidably fit, in the Slot. 34. so. that, the cable ii]. is always positioned, between the light tube 3] and the coated portion. of. thearmor tube.

Two'electrical. wires W! and W2. lead from socket 3.5a, through the; disk. 3 5.tc. the connector 25 and two wires W3, Wt. lead from the lower socket 3E0. through the. cable it. and disk 35 to the. connector 25.. There is an excesslength. of

wires. Wl-W,i; between the. upper. disk 3.5 and the. connector. 25. for the purpose: to be dc scribed.

As best seen in Figs. 1 and 3, the connector 25 isfixedrtothe fla-ngedztop-endof a sleevedE, as by screws 46, the sleeve slidably or telescopically fitting on the-top end of, the armor tube 3 and carrying a radial guide screw 4153. which also The . from the lower end of the sleeve: to. permitgthe: 81637.6 tube.

axially moved on the armor tube until the screw is removed from the slot, to permit the sleeve to be rotated relative to the armor tube until the prongs 22 are engaged in or disengaged from the socket 2|.

From the foregoing, it will be apparent that not only is the lighting tube fully protected by the armor tube, but it is extremely simple to quickly install and remove the lighting tube. To remove it, it is only necessary to rotate the armor tube and sleeve, with its carried connector, to the left, or counterclockwise, freeing the prongs from the socket. Being telescopically mounted on the armor tube, the sleeve may be moved downwardly on the armor tube to provide suflicient clearance between the prongs and the socket 2! to enable them to be disengaged and to enable the armor tube to be lifted from the position in ferrule 2? without disconnecting the wires WIW4. The sleeve and the armor tube with its contents may be then moved outwardly from the cabinet and the armor tube to be withdrawn from its contained unit, after which a new lighting tube may be inserted between the sockets 35a, 36a. The armor tube is again installed and the entire unit may be placed back into the cabinet, after which the prongs of the connector are locked in the socket 25.

We claim:

1, A lighting unit for a display case or the like comprising: an electrical supply socket adapted to be fixedly mounted in said case in position spaced above the floor thereof, a transparent armor tube adapted to be disposed axially between said floor and socket, the tube being shorter than the distance from said floor to the socket, a sleeve telescopically mounted on the upper end of the tube, an electrical connector carried on the sleeve for locking engagement in said socket, a lighting element mounted in the armor tube, said element comprising a lower disk and an upper disk each shaped to slidably fit in the armor tube, a fluorescent light tube receiving socket carried by each disk, a substantially rigid tube secured to and holding the disks spaced apart longitudinally of the armor tube,

electrical wires leading from the connector to the socket carried by the upper disk and wires leading through said substantially rigid tube to the socket carried by the lower disk; there being an excess length of said wires between the upper disk and the connector to allow the sleeve to be axially removed from the armor tube without disconnecting said wires.

2. A lighting unit for a display case or the like comprising an electrical supply socket adapted to be fixedly mounted in the case, a positioning plate adapted to be fixedly mounted in the case opposite the socket, a transparent armor tube adapted to be disposed axially between the socket and plate, the armor tube being shorter than the distance between said socket and plate, a sleeve telescopically mounted on the upper end of the tube, an electrical connector carried on. the top end of the sleeve for locking engagement in said socket, an elongated electrical lighting tube mounted longitudinally in said armor tube, and wires leading from the connector to the lighting tube, there being an excess length of said wires between the connector and lighting tube whereby to allow the sleeve to be axially removed from the armor tube without disconnecting said wires.

3. A lighting unit for a display case or the like comprising an electrical supply socket adapted to be fixedly mounted in the case, a positioning plate adapted to be fixedly mounted in the case opposite the socket, a transparent armor tube adapted to be disposed axially between the socket and plate, the armor tube being shorter than the distance between said socket and plate and having a longitudinally disposed guide slot extending through its top end from a point adjacent said end, a sleeve telescopically mounted on the upper end of the tube, an electrical connector carried on the top end of the sleeve for locking engagement in said socket, a pair of light sockets slidably mounted in the armor tube, an elongated electrical lighting tube disposed longitudinally in said armor tube between said light sockets, wires leading from the connector to the light sockets, there being an excess length of said wires between the connector and light sockets whereby to allow the sleeve to be axially removed from the armor tube without disconnecting said wires, and a radial projection on the top light socket slidably fitting in said guide slot.

4. In a display cabinet having a top wall, a bottom wall, side walls and a doorway in one of the side walls, an electrical socket member fixedly carried by the top wall adjacent the doorway, a cup-shaped positioning member secured to the floor directly under the socket member, a transparent armor tube having its bottom end fitted in the positioning member and having its open top end terminating short of the socket member, a sleeve telescopically mounted on the top end of the armor tube, an electrical connector carried by the sleeve for locking en gagement with the socket member, a lighting element removably mounted in the armor tube comprising a fluorescent tube light, end sockets for the latter tube, disks carrying the respective end sockets, a substantially rigid tube connected to and holding the disks in spaced relation to each other longitudinally of the armor tube, and wires connecting the end sockets to the connector.

5. In a display cabinet having a top wall, a bottom wall, side walls and a doorway in one of the side walls, an electrical socket member fixedly carried by the top wall adjacent the doorway, a cup-shaped positioning member secured to the floor directly under the socket member, a transparent armor tube having its bottom end fitted in the positioning member and having its open top end terminating short of the socket member, a sleeve telescopically mounted on the top end of the armor tube, an electrical connector carried by the sleeve for locking engagement with the socket member, a lighting element removably mounted in the armor tube comprising a fluorescent tube light, end sockets for the latter tube, disks carrying the respective end sockets, a substantially rigid tube connected to and holding the disks in spaced relation to each other longitudinally of the armor tube, and Wires connecting the end sockets to the connector, the wires having sufficient excess length within the armor tube to permit the sleeve to be removed from the armor tube Without disconnecting the wires.

6. The device of claim 4 wherein the outer portion of the armor tube towards the doorway is coated with a light reflective material, wherein the upper end of the armor tube is longitudinally slotted and wherein the upper disk has a radial projection slidably fitting in said slot whereby to retain the lighting element in position with the substantially rigid tube disposed between the lighting tube and said outer portion of the armor tube. ggi

HERBERT E. GRINDSTAFF. 5 FLOYE J. BEARDEN. 2,347,174 REFERENCES CITED 14061145 The following references are of record in the file of this patent: 10 Number I 6 UNITED STATES PATENTS Name Date Miller Mar. 29, 1910 Coy Sept. 11, 1934 Goalstone June 20, 1939 Cross et a1. Apr. 25, 1944 Holmes Aug. 20, 1946 FOREIGN PATENTS Country Date France Mar. 29, 1929 

